Front end-?need some advice

[rlane]

I am still pretty new to DE's, have done 7 or 8 in the last two years. I just got a new ride last fall in the form of a 73 RS clone. At Mid-Ohio last weekend I had a great time and feel my skills have improved a lot but as I have begun pushing my level I am experiencing the same (push) as I start to exit turns. Specifically, I and two instructors who I let drive it felt that it had good front tire grip on entry but as soon as we start to dial in some throttle the front end seems to "wash out". We dropped the hot tire pressure from 35 to 33.5 (new Toyo RA-1's all around) with maybe a little improvement. I know there must be a ton of variables to change but I am just starting out and appreciate any advice on where to start.
The car is lowered, has 22 mm sway bars f/r, 22mm/27 mm torsion bars, Koni orange shocks and a Stable Energies truss.
Thanks

[cstreit]

Remember that when adding throttle you are making a weight shift to the rear of the car, taking weight off the front.

Try turning in a bit later so as to minimize the part/throttle turning. But also you may:

- Soften the front sway bar a bit.
- Stiffen the rear bar.
- Increase the rear spring rates or compression valving.

[rlane]

Thanks Chris, I thought the 22 mm say bars both front and rear were a little much..I think my 78SC has 19 up front.
What size would you recommend..or maybe go the adjustable route?
Both of the instructors tried different turn ins..din't seem to make that much difference. The car has a pretty strong motor..so it definetely will settle the weight to the rear but even with a pretty smooth throttle feed in we noticed it losing grip up front.

[Zeke]

Richard, long time no hear from. For those of you that didn't catch it, Richard graciously looked at my 911 for me before I sent the money to KY. The car was exactly as he described it.

That RS clone sounds like it's pulling the wheels off the ground. No wonder you can't steer it! Streit knows his stuff. You might try adjustable bars to soften the front a little. Your Tbar choice seems in the range the guys I talk to use. And, I'll bet he's right on the shocks. You have pretty stiff bars for Koni reds, IMHO. Did you dial them up?

Last suggestion is to put a little weight back in the front. Where is your battery?

[rlane]

Hey Milt...I keep seeing all sorts of bits about that "S"..I think it will be a supercar before you are done!
Yes, I have the Konis dialed up...but not sure if I have gotten them all the way, need to check. I still have the twin batterys up front, may try the Optima in the well change, I even put the spare back in last weekend. I may try the adjustable sway bar, I see our host has a new brand.
Geez but this car is fun though...It is capable of far more than I am on the track but when I pull in from sessions I am just one big wide grin

[cstreit]

Rich,

What are your alignment settings currently (toe and camber)?

[Noel]

Richard,

I was also at Mid-Ohio last weekend and ran in the White group. I'm not sure what group you were in, but I have always used my gas pedal to control turn-in grip. The best example is while going through the Keyhole (Relatively slow turn). Just over the rise, let the throttle breath a little. You will note that the front will bite and the car will begin the rotate. Get back on the gas to control the rotation and then accelerate out of the turn.
Look for my car at future events. I always try to run a couple times a year at Mid-Ohio.

BTW, How did your tires hold up against the cheese graters that used to be the concrete patches?

[rlane]

Chris..I don't know the alignment info but will try to get it. Had the car set up by a very well regarded local shop that does a fair number of p-cars as well as other track cars...good idea to know that info though...I'll post it when I get it.
Noel. I was in White as well, Silver 73 w/Ducktail, fairly loud as my AJ-USA sport muffler seems to be on the low side of baffling..
I had brand new Toyo RA-1's and they are about 50% now! Wow but you are right..with a little feathering in both Keyhole and even more in Carousel the bite/rotation were a real visceral experience!
My problem is that when I do get back on the gas the front end pushes out, even if I "squeeze softly". This was definetely worse in the right hander post Madness and in the right hander before Thunder Valley

[rlane]

I did check with the alignment folks and they set it up basically per factory specs and NOT for the tracxk. Now I know I have to tell them to put negative camber and toe in on . 'Course I geuss I could have been running those RA-1's in wild street racing....

[cstreit]

Toe out in front will help the turn in. Try like 1/16". Maybe 2 degrees of camber....

[Noel]

Good luck getting 2 degrees of negative camber in the front with a stock car! The most I could get was .8 degrees with the stock strut top plates. As far as toe-out goes, it will help turn in, but I would be hesitent to toe-out a highspeed dual purpose track car. For autocross it is preferred though. However, the car will loose straight line stability. I have mine set for zero to extremely slight toe-in in the front.
BTW, adding a front strut brace will also help the front to bite a bit more, by holding alignment/camber settings more consistent.

Good luck,

[cstreit]

Noel,

I got 2.5 degrees out of a stock setup!

Yes straight line stability will be a bit less, but if you add a bit more castor, it will help stability. (Though I never really noticed the difference, even at 140MPH) and I run 3/16" toe out!

THe strut brace is only a small aid compared to the proper alignment settings, as it is only designed to hold those settings, not improve on them.

[Noel]

WOW, how the hell did you do that? That is extremely unusual from all I have talked with (At least with the 78-89 body cars). Most had to go with slotted towers and using strut braces to pull the towers together.

The bottom line is, it is a big compromise. What works well at the track doesn't always work well on the street. The place you really notice a difference with toe-out is the street. The car will follow every rut on the street and will be very darty. While I only drive my car a couple thousand miles a year on the street I still consider it a dual use car and was unable to live with such an alignment.

Good luck Richard with your choice. And keep in mind you can easily change alignment settings back if you don't like them... or at least pay someone to do this.

[cstreit]

Noel,

Well good question... Funny thing is on the rear I could get 1.5 on one side and only 1.2 on the other.... Each car seems different. Perhaps my upper strut plates were different?

[DanS911]

I cant get passed -1 in the front of my '76 stock

[cstreit]

Huh... I wonder what's different about my 70 'S?

[daloff]

Definately concur with Chris on the anti-roll bar size (sway bar). You are sprung too tight in the front and too loose in the rear. What is the weight of the car ? Have you had it corner balanced ? Also what rates do you have on those Koni(s) ?

Cheers,
David

[rlane]

Lots of great input!
I do have a strut brace in place. This is turning into more and more track car with street driving just to and from the shop and a few back round testing sessions. The 78SC is now the cruiser.
David , the car was corner balanced before I bought it last year..I may borrow a friends scales and see what it is like now (Noel, he was the fellow that had his 968's engine let go between 2-3 at Mid Ohio last wekend..$20K club racing engine with less than 1000 miles on it!) Car is estimated at 2200 3's, would be fun to get the actual weight. I am just starting to look at the Konis...not at all sure how to determine the rates?

[daloff]

Richard -

If you are only at 2200 lbs I would definately change to 21mm tbar on the front and at least 30 on the rear.

I'd ditch the Konis and go to a Bilstein setup

[rlane]

2200 is based on the PO's corner balancing...could be more but wouldn't that be about right for a 73 that styarted life as a "E", lightweight Recaro's, no frills?
I'll look for T-bars at hershey...where I am headed..NOW!